HSPA13 facilitates NF-κB-mediated transcription and attenuates cell death responses in TNFα signaling.
Ontology highlight
ABSTRACT:
SUBMITTER: Gao C
PROVIDER: S-EPMC8494447 | biostudies-literature |
REPOSITORIES: biostudies-literature
Similar Datasets
Project description:The lindenane-type sesquiterpenoid chlojaponilactone B (1), isolated from Chloranthus japonicus, has been reported to possess anti-inflammatory properties. The present study aimed to further explore the molecular mechanisms underlying the anti-inflammatory activity of 1. RNA-seq analyses revealed the significant changes in the expression levels of genes related to multiple inflammatory pathways upon treatment of lipopolysaccharide (LPS)-induced RAW 264.7 murine macrophages with 1. Real time PCR (RT-PCR) and Western blotting were used to confirm the modulations in the expression of essential molecules related to inflammatory responses. Compound 1 inhibited toll like receptor 4 (TLR4) and myeloid differentiation factor 88 (MyD88) activation upon LPS stimulation, influencing the expression of NF-κB and pro-inflammatory mediators. Molecular docking studies showed that 1 bound to TLR4 in a manner similar to that of TAK-242, a TLR4 inhibitor. Moreover, our results showed that 1 suppressed inflammatory responses by inhibiting TLR4 and subsequently decreasing reactive oxygen species (ROS) generation, downregulating the NF-κB, thus reducing the expression of the pro-inflammatory cytokines iNOS, NO, COX-2, IL-6 and TNF-α; these effects were similar to those of TAK-242. We proposed that 1 should be considered as a potential anti-inflammatory compound in future research.
| S-EPMC6832138 | biostudies-literature
Project description:Monocyte-derived antigen presenting cells (APC) are central mediators of the innate and adaptive immune response in inflammatory diseases. As such, APC are appropriate targets for therapeutic intervention to ameliorate certain diseases. APC differentiation, activation and functions are regulated by the NF-κB family of transcription factors. Herein, we examined the effect of NF-κB inhibition, via suppression of the IκB Kinase (IKK) complex, on APC function. Murine bone marrow-derived macrophages and dendritic cells (DC), as well as macrophage and DC lines, underwent rapid programmed cell death (PCD) after treatment with several IKK/NF-κB inhibitors through a TNFα-dependent mechanism. PCD was induced proximally by reactive oxygen species (ROS) formation, which causes a loss of mitochondrial membrane potential and activation of a caspase signaling cascade. NF-κB-inhibition-induced PCD of APC may be a key mechanism through which therapeutic targeting of NF-κB reduces inflammatory pathologies.
| S-EPMC3887388 | biostudies-literature
Project description:In Drosophila, Toll/NF-κB signaling plays key roles in both animal development and in host defense. The activation, intensity, and kinetics of Toll signaling are regulated by posttranslational modifications such as phosphorylation, SUMOylation, or ubiquitination that target multiple proteins in the Toll/NF-κB cascade. Here, we have generated a CRISPR-Cas9 edited Dorsal (DL) variant that is SUMO conjugation resistant. Intriguingly, embryos laid by dlSCR mothers overcome dl haploinsufficiency and complete the developmental program. This ability appears to be a result of higher transcriptional activation by DLSCR. In contrast, SUMOylation dampens DL transcriptional activation, ultimately conferring robustness to the dorso-ventral program. In the larval immune response, dlSCR animals show an increase in crystal cell numbers, stronger activation of humoral defense genes, and high cactus levels. A mathematical model that evaluates the contribution of the small fraction of SUMOylated DL (1-5%) suggests that it acts to block transcriptional activation, which is driven primarily by DL that is not SUMO conjugated. Our findings define SUMO conjugation as an important regulator of the Toll signaling cascade, in both development and host defense. Our results broadly suggest that SUMO attenuates DL at the level of transcriptional activation. Furthermore, we hypothesize that SUMO conjugation of DL may be part of a Ubc9-dependent mechanism that restrains Toll/NF-κB signaling.
| S-EPMC9252280 | biostudies-literature
Project description:The sodium-iodide symporter (NIS) mediates transport of iodide across the basolateral membrane of thyroid cells. NIS expression in thyroid cancer (TC) cells allows the use of radioactive iodine (RAI) as a diagnostic and therapeutic tool, being RAI therapy the systemic treatment of choice for metastatic disease. Still, a significant proportion of patients with advanced TC lose the ability to respond to RAI therapy and no effective alternative therapies are available. Defective NIS expression is the main reason for impaired iodide uptake in TC and NIS downregulation has been associated with several pathways linked to malignant transformation. NF-κB signaling is one of the pathways associated with TC. Interestingly, NIS expression can be negatively regulated by TNF-α, a bona fide activator of NF-κB with a central role in thyroid autoimmunity. This prompted us to clarify NF-kB's role in this process. We confirmed that TNF-α leads to downregulation of TSH-induced NIS expression in non-neoplastic thyroid follicular cell-derived models. Notably, a similar effect was observed when NF-κB activation was triggered independently of ligand-receptor specificity, using phorbol-myristate-acetate (PMA). TNF-α and PMA downregulation of NIS expression was reverted when NF-κB-dependent transcription was blocked, demonstrating the requirement for NF-kB activity. Additionally, TNF-α and PMA were shown to have a negative impact on TSH-induced iodide uptake, consistent with the observed transcriptional downregulation of NIS. Our data support the involvement of NF-κB-directed transcription in the modulation of NIS expression, where up- or down-regulation of NIS depends on the combined output to NF-κB of several converging pathways. A better understanding of the mechanisms underlying NIS expression in the context of normal thyroid physiology may guide the development of pharmacological strategies to increase the efficiency of iodide uptake. Such strategies would be extremely useful in improving the response to RAI therapy in refractory-TC.
| S-EPMC7015378 | biostudies-literature
Project description:BackgroundStephania yunnanensis H. S. Lo is widely used as an antipyretic, analgesic and anti-inflammatory herbal medicine in SouthWest China. In this study, we investigated the anti-inflammatory activity and mechanism of sinoacutine (sino), one of the primary components extracted from this plant.MethodsA RAW264.7 cell model was established using lipopolysaccharide (LPS) induced for estimation of cytokines in vitro, qPCR was used to estimate gene expression, western blot analysis was used to estimate protein level and investigate the regulation of NF- κB, JNK and MAPK signal pathway. In addition, an acute lung injury model was established to determine lung index and levels of influencing factors.ResultsUsing the RAW264.7 model, we found that sino reduced levels of nitric oxide (NO), tumour necrosis factor-α (TNF-α), interleukin (IL)-1β and prostaglandin E2 (PGE2) but increased levels of IL-6. qPCR analysis revealed that sino (50, 25 μg/ml) inhibited gene expression of nitric oxide synthase (iNOS). western blot analysis showed that sino significantly inhibited protein levels of both iNOS and COX-2. Further signalling pathway analysis validated that sino also inhibited phosphorylation of p65 in the NF-κB and c-Jun NH2 terminal kinase (JNK) signalling pathways but promoted the phosphorylation of extracellular signal regulated kinase (ERK) and p38 in the MAPK signalling pathway. In addition, in a mouse model induced by LPS, we determined that sino reduced the lung index and the levels of myeloperoxidase (MPO), NO, IL-6 and TNF-α in lung tissues and bronchoalveolar lavage fluid (BALF) in acute lung injury (ALI).ConclusionTaken together, our results demonstrate that sino is a promising drug to alleviate LPS-induced inflammatory reactions.
| S-EPMC8605577 | biostudies-literature
Project description:ObjectiveDARPP-32 is a frequently amplified and overexpressed gene that promotes several oncogenic functions in gastric cancer. Herein, we investigated the relationship between Helicobacter pylori infection, proinflammatory NF-κB activation and regulation of DARPP-32.DesignThe study used in vivo and in vitro experiments. Luciferase reporter, quantitative real-time PCR, immunoblot, chromatin immunoprecipitation (ChIP), cell viability, H. pylori infection, tissue microarrays and immunohistochemical assays were used.ResultsOur results indicated that H. pylori infection increased the DARPP-32 mRNA and protein levels in gastric cancer cell lines and gastric mucosa of mice. H. pylori infection increased the activity of NF-κB reporter and p-NF-κB (S536) protein level in vitro and in vivo. To investigate the transcriptional regulation of DARPP-32, we cloned a 3019 bp of the DARPP-32 promoter into the luciferase reporter (pGL3-Luc). Both H. pylori infection and tumour necrosis factor-α treatment induced DARPP-32 reporter activity (p<0.01). Using deletion constructs of DARPP-32 promoter and ChIP assay, we demonstrated that the sequence -996 to -1008 bp containing putative NF-κB-binding sites is the most active region. The induction of DARPP-32 expression by H. pylori infection counteracted H. pylori-induced cell death through activation of serine/threonine-specific protein kinase (AKT), as determined by ATP-Glo and clonogenic survival assays. Immunohistochemistry analysis demonstrated a significant positive correlation between NF-κB and DARPP-32 expression levels in gastric cancer tissues (r2=0.43, p<0.01).ConclusionsGiven the high frequency of DARPP-32 overexpression and its prosurvival oncogenic functions, the induction of DARPP-32 expression following H. pylori infection and activation of NF-κB provides a link between infection, inflammation and gastric tumourigenesis.
| S-EPMC5334457 | biostudies-literature
Project description:Lys63-linked polyubiquitination of transforming growth factor-β-activated kinase 1 (TAK1) has an important role in tumor necrosis factor-α (TNFα)-induced NF-κB activation. Using a functional genomic approach, we have identified ubiquitin-specific peptidase 4 (USP4) as a deubiquitinase for TAK1. USP4 deubiquitinates TAK1 in vitro and in vivo. TNFα induces association of USP4 with TAK1 to deubiquitinate TAK1 and downregulate TAK1-mediated NF-κB activation. Overexpression of USP4 wild type, but not deuibiquitinase-deficient C311A mutant, inhibits both TNFα- and TAK1/TAB1 co-overexpression-induced TAK1 polyubiquitination and NF-κB activation. Notably, knockdown of USP4 in HeLa cells enhances TNFα-induced TAK1 polyubiquitination, IκB kinase phosphorylation, IκBα phosphorylation and ubiquitination, as well as NF-κB-dependent gene expression. Moreover, USP4 negatively regulates IL-1β-, LPS- and TGFβ-induced NF-κB activation. Together, our results demonstrate that USP4 serves as a critical control to downregulate TNFα-induced NF-κB activation through deubiquitinating TAK1.
| S-EPMC3136563 | biostudies-literature
Project description:This study explored the mechanism by which metformin (Met) inhibits osteoclast activation and determined its effects on osteoarthritis (OA) mice. Bone marrow-derived macrophages were isolated. Osteoclastogenesis was detected using tartrate-resistant acid phosphatase (TRAP) staining. Cell proliferation was evaluated using CCK-8, F-actin rings were detected by immunofluorescence staining, and bone resorption was detected using bone slices. Nuclear factor kappa-B (NF-κB) and nuclear factor of activated T-cell cytoplasmic 1 (NFATc1) were detected using luciferase assays, and the adenosine monophosphate-activated protein kinase (AMPK), NF-κB, and mitogen-activated protein kinase (MAPK) signaling pathways were detected using western blotting. Finally, expression of genes involved in osteoclastogenesis was measured using quantitative polymerase chain reaction. A knee OA mouse model was established by destabilization of the medial meniscus (DMM). Male C57BL/6J mice were assigned to sham-operated, DMM+vehicle, and DMM+Met groups. Met (100 mg/kg/d) or vehicle was administered from the first day postoperative until sacrifice. At 4- and 8-week post OA induction, micro-computed tomography was performed to analyze microstructural changes in the subchondral bone, hematoxylin and eosin staining and Safranin-O/Fast Green staining were performed to evaluate the degenerated cartilage, TRAP-stained osteoclasts were enumerated, and receptor activator of nuclear factor κB ligand (RANKL), AMPK, and NF-κB were detected using immunohistochemistry. BMM proliferation was not affected by Met treatment below 2 mM. Met inhibited osteoclast formation and bone resorption in a dose-dependent manner in vitro. Met suppressed RANKL-induced activation of p-AMPK, NF-κB, phosphorylated extracellular regulated protein kinases (p-ERK) and up-regulation of genes involved in osteoclastogenesis. Met reversed decreases in BV/TV, Tb.Th, Tb.N, and CD, and an increase in Tb.Sp at 4 weeks postoperatively. The number of osteoclasts and OARSI score were decreased by Met without effect on body weight or blood glucose levels. Met inhibited RANKL, p-AMPK, and NF-κB expression in early OA. The mechanism by which Met inhibits osteoclast activation may be associated with AMPK/NF-κB/ERK signaling pathway, indicating a novel strategy for OA treatment.
| S-EPMC8675877 | biostudies-literature
Project description:ObjectivesA role for the type II arginine methyltransferase PRMT5 in various human diseases has been identified. In this study, the potential mechanism underlying the involvement of PRMT5 in the pathological process leading to osteoarthritis (OA) was investigated.MethodsPRMT5 expression in cartilage tissues from patients with OA and control individuals was assessed by immunohistochemical staining. The regulatory and functional roles of PRMT5 in the chondrocytes of patients with OA and control individuals were determined by western blotting and reverse transcription polymerase chain reaction. The effects of the PRMT5 inhibitor EPZ on interleukin-1β-induced inflammation were examined in the chondrocytes of patients with OA and in the destabilized medial meniscus (DMM) of a mouse model of OA.ResultsPRMT5 was specifically upregulated in the cartilage of patients with OA. Moreover, adenovirus-mediated overexpression of PRMT5 in human chondrocytes caused cartilage degeneration. This degeneration was induced by elevated expression levels of matrix-degrading enzymes (matrix metalloproteinase-3 (MMP-3) and matrix metalloproteinase-13 (MMP-13)) in chondrocytes. The activation of the MAPK and nuclear factor κB signaling pathways was evidenced by elevated levels of p-p65, p-p38, and p-JNK. These effects were attenuated by inhibiting the expression of PRMT5. In the mouse model, EPZ inhibited PRMT5 expression, thus protecting mouse cartilage from DMM-induced OA.ConclusionsOur results demonstrate that PRMT5 is a crucial regulator of OA pathogenesis, implying that EPZ has therapeutic value in the treatment of this cartilage-destroying disease.
| S-EPMC7650297 | biostudies-literature
Project description:Our aim was to investigate the effects of phycocyanin (PC) on bleomycin (BLM)-induced pulmonary fibrosis (PF). In this study, C57 BL/6 wild-type (WT) mice and toll-like receptor (TLR) 2 deficient mice were treated with PC for 28 days following BLM exposure. Serum and lung tissues were collected on days 3, 7 and 28. Data shows PC significantly decreased the levels of hydroxyproline (HYP), vimentin, surfactant-associated protein C (SP-C), fibroblast specific protein-1 (S100A4) and α-smooth muscle actin (α-SMA) but dramatically increased E-cadherin and podoplanin (PDPN) expression on day 28. Moreover, PC greatly decreased the levels of interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α) and myeloperoxidase (MPO) at the earlier time. Reduced expression of key genes in the TLR2 pathway was also detected. Compared with WT mice, TLR2-deficient mice exhibited less injury, and the protective effect of PC was partly diminished in this background. These data indicate the anti-fibrotic effects of PC may be mediated by reducing W/D ratio, MPO, IL-6, TNF-α, protecting type I alveolar epithelial cells, inhibiting fibroblast proliferation, attenuating epithelial-mesenchymal transitions (EMT) and reducing oxidative stress. The TLR2-MyD88-NF-κB pathway plays an important role in PC-mediated reduction in pulmonary fibrosis.
| S-EPMC5517415 | biostudies-literature